A turbofan engine as described above is conventionally equipped with rotor blades that introduce air into an engine body, and guide vanes that are stator vanes straightening a flow of the air which is introduced by the rotor blades.
In order to meet requirements for increasing bypass ratio with an objective of improving fuel efficiency of a turbofan engine of recent years, fan diameter is tend to be enlarged. Accordingly, it becomes urgent to reduce the weight of the turbofan engine.
The weight of the guide vane which is a stator vane straightening the flow of air, is reduced by making it a composite vane consisting of a composite material of a thermosetting resin such as epoxy resin and reinforced fibers such as carbon fibers, for example. In the case of the guide vane consisting of a composite material like this, the wear resistance is lower as compared with a metallic guide vane. Therefore, abrasion is avoided by bonding a metal sheath for preventing erosion to a leading edge section (a leading edge and a vicinity of the leading edge) which is especially easily worn, by an adhesive (refer to Patent Documents 1 and 2, for example).
Such metallic sheath for preventing erosion sometimes suffers so-called FOD (Foreign Object Damage), in which the metal sheath is damaged by collisions with foreign objects such as small stones which are sucked into the engine. In order to suppress damages to the metal sheath at the time of collision with foreign objects, and to make the adhesive be easily peeled off at a time of replacement of the metal sheath which suffers the FOD, the metal sheath is bonded using a soft adhesive as the adhesive (refer to Patent Document 3, for example).
When the metal sheath is bonded to the leading edge section using the soft adhesive as described above, it is required to keep the thickness of the layer of the soft adhesive uniform at the time of applying the soft adhesive. As the art of making the thickness of the soft adhesive uniform, there is known a method, in which studs with the same height as the thickness of the soft adhesive are formed on the surface, on which the soft adhesive is applied (refer to Patent Document 4, for example).